The Tayana 48 DS
Specs & Key Performance Indicators

The Tayana 48 DS sailboat, a centre-cockpit cutter, was designed by American naval architect Bob Perry. It is built by Ta Yang Yacht Building Co Ltd, located in Kaohsiung, Taiwan.

a Tayana 48 DS at anchor

Published Specification for the Hunter 48DS Sailboat

Keel & Rudder Configuration: Fin keel with skeg-hung rudder
Hull Material: Fiberglass
Length Overall: 14.63 meters (48'0")
Waterline Length: 12.19 meters (40'0")
Beam: 4.42 meters (14'6")
Draft: 1.83 meters (6'0")
Rig Type: Cutter rig
Displacement: 15,422 kilograms (34,000 pounds)
Ballast: 5,443 kilograms (12,000 pounds)
Designer: Bob Perry
Builder: Ta Yang Yacht Building Co., Ltd.
Year First Built: 1992
Year Last Built: Ongoing
Number Built: Over 200 units

Published Design Ratios for the Hunter 48DS Sailboat
The Key Performance Indicators (KPIs)

The Tayana 48 DS sailboat's design ratios provide insight into its theoretical sailing characteristics:

Sail Area/Displacement Ratio (19.8): This ratio suggests the Tayana 48 DS has reasonably good performance capabilities. It is not underpowered and should perform well in various wind conditions, though it does not fall into the high-performance category.

Ballast/Displacement Ratio (33.4): This indicates a moderately stiff boat, capable of standing up to the wind. However, this ratio does not account for the ballast's location. A boat with a shallow draft keel may be less stiff compared to one with a bulb keel, even if both have the same ballast/displacement ratio.

Displacement/Length Ratio (239.6): Falling into the moderate displacement category, the Tayana 48 DS requires a moderate amount of sail area to reach its design hull speed. This balance suggests it is neither too light nor too heavy, making it suitable for a variety of sailing conditions.

Comfort Ratio (36.1): This ratio indicates a moderate bluewater cruising boat. It should provide a comfortable motion in most conditions, though it may not be as stable as heavier bluewater boats. Ted Brewer's Comfort Ratio tends to favor heavy displacement, narrow-beamed vessels with long overhangs, so modern light-displacement, beamy cruisers with plumb bows may not score as well despite having good bluewater capability.

Capsize Screening Formula (1.8): With a value below 2.0, the Tayana 48 DS is considered suitable for ocean passages. This low value suggests a reduced vulnerability to capsizing, making it a safer choice for bluewater cruising.

Here's how to calculate the KPIs yourself - without having to wrestle with the mathematics...

Design Ratios: Notes of Caution...

The Sail Area/Displacement Ratio (SA/D): This ratio provides an estimate of the sail power relative to the boat's weight, which can indicate potential speed in various wind conditions. But it doesn't account for the efficiency of the sail plan, the rigging, or the skill of the crew. Real-world performance can vary significantly based on these factors.

The Ballast/Displacement Ratio (B/D): This ratio gives an idea of the boat's stability and stiffness, which is crucial for handling and safety. But it doesn't consider the distribution of the ballast or the hull shape, both of which can greatly affect stability. A high B/D ratio alone doesn't guarantee a stable boat if the ballast is poorly distributed.

The Displacement/Length Ratio (D/L): This ratio helps predict the boat's speed potential and its behaviour in different sea conditions. But it doesn't account for the hull design or the boat's overall weight distribution. Two boats with the same D/L ratio can perform very differently if their hull shapes are different.

The Comfort Ratio (CR): This ratio estimates the boat's motion comfort in a seaway, which is important for long passages. But it doesn't consider the boat's interior layout, which can also affect comfort. Additionally, personal tolerance to motion varies, so a boat that is comfortable for one person might not be for another.

The Capsize Screening Formula (CSF): This formula assesses the likelihood of a boat capsizing in heavy seas, which is critical for offshore safety. But it doesn't take into account the boat's handling characteristics or the skill of the crew. A boat with a low CSF can still capsize if poorly handled in severe conditions.

General Limitations

Static Nature: These ratios are static measurements and don't account for dynamic factors like wave action, wind gusts, or crew actions.

Simplification: They simplify complex interactions into single numbers, which can be misleading. Real-world performance is influenced by a multitude of factors that these ratios can't fully capture.

Context: The context in which the boat is used (e.g., coastal cruising vs. offshore racing) can greatly affect how these ratios should be interpreted.

In summary, while these ratios provide valuable insights into the theoretical performance characteristics of a sailboat, they should be used as part of a broader assessment that includes practical experience, sea trials, and expert advice.

This article was written with the assistance of Gemini, a large language model developed by Google. Gemini was used to gather information, summarize research findings, and provide suggestions for the content and structure of the article.